Equivalent & Substitute Parts for 3AB 5 Ceramic Fuse

Part Overview

The 3AB 5 is a 5A 250VAC ceramic cartridge fuse manufactured by Bel Fuse Inc., designed for fast-blow protection in AC/DC applications. This fuse requires a dedicated holder (3AB or 3AG type) and is housed in a 1/4" x 1-1/4" form factor. The main part number 3AB 5 is currently listed as obsolete, making identification of active equivalent parts essential for ongoing system maintenance and component procurement.

Substiute Parts

3AB 5

Bel Fuse Inc.In Stock: 8633AB 5 Datasheet

Current PartRFQ

3AB 5-R

Bel Fuse Inc.In Stock: 19173AB 5-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The 3AB 5-R serves as a direct substitute for the obsolete 3AB 5 based on the following critical parameters:

• Current Rating: Both parts are rated at 5 A
• Voltage Rating: Both are rated for 250 V AC
• Fuse Type and Response: Both are ceramic cartridge fuses with fast-blow characteristics
• Physical Form Factor: Both use the identical 3AB/3AG holder package with 1/4" x 1-1/4" dimensions
• Breaking Capacity: Both maintain 200 A breaking capacity at rated voltage
• Melting I²t: Both have identical melting I²t value of 63
• Operating Temperature: Both operate across -55°C ~ 125°C range

The 3AB 5-R is the active production equivalent, with improved RoHS3 compliance and marginally lower DC cold resistance (0.018 Ohms vs. 0.02 Ohms).

Parameter Comparison

Engineering Selection Recommendations

The 3AB 5-R is the appropriate replacement for the obsolete 3AB 5 ceramic fuse. Both parts maintain identical electrical and mechanical specifications, ensuring direct compatibility in existing 3AB/3AG holder assemblies. The 3AB 5-R offers the additional advantage of ROHS3 compliance, meeting current regulatory requirements for new designs and procurement cycles. All required certifications (CE, CSA, PSE) are maintained across both variants, with the 3AB 5-R adding cURus certification. The marginal reduction in DC cold resistance (0.018 Ohms vs. 0.02 Ohms) presents no functional impact on circuit performance.

Frequently Asked Questions (FAQ)

Q: Can the 3AB 5-R be used as a direct replacement for the 3AB 5?

A: Yes. Both fuses share identical current rating (5 A), voltage rating (250 V AC), fuse type (ceramic cartridge), response time (fast blow), physical dimensions (1/4" x 1-1/4"), breaking capacity (200 A), and melting I²t (63). They are mechanically and electrically interchangeable in any 3AB or 3AG holder assembly.

Q: What holder types are compatible with these fuses?

A: Both the 3AB 5 and 3AB 5-R require a dedicated fuse holder of type 3AB or 3AG. The fuses are not suitable for use in standard blade or cartridge holders designed for other form factors.

Q: Are there compliance differences between the two parts?

A: The 3AB 5-R is ROHS3 compliant, while the 3AB 5 is RoHS non-compliant. Both maintain CE, CSA, and PSE certifications. The 3AB 5-R adds cURus certification. For new system designs or procurement requiring RoHS compliance, the 3AB 5-R is the appropriate selection.

Q: What is the significance of the DC cold resistance difference?

A: The 3AB 5-R has a DC cold resistance of 0.018 Ohms compared to 0.02 Ohms for the 3AB 5. This minor difference (0.002 Ohms) has negligible impact on circuit operation and does not affect substitution suitability.

Q: What is the operating temperature range for these fuses?

A: Both fuses operate across -55°C to 125°C, providing consistent thermal performance across standard industrial and commercial temperature ranges.